USB Cable: 95cm long; Energy Usage: approx 2.5W * Heating Plate: 82mm diameter; Systems: Windows 98SE / Me / 2000 / XP / Vista * Whole Unit: 135mm x 63mm (diameter x height) * Weight: 233g; Power Source: Computer USB for warming plate and hub, button battery for clock * Package Contents: 1 x USB Cup Warmer; 1 x Instruction Sheet(English Chinese)